Abstract: A device for tensioning chains on crawler-type or tracked vehicles, in particular the chains of hydraulic excavators, comprises a first cylinder arranged in an area of the chassis for the tracked vehicle, and operatively connected via a piston rod to a guide wheel to tension the chain. A second cylinder forms a spring cylinder and is operatively connected to the first cylinder. The second cylinder concentrically encloses the first cylinder to form a double cylinder and each cylinder is provided with a separate hydraulic connection. At startup of the tracked vehicle, the hydraulic connections of the double cylinder are admitted with a specifiable pre-tensioning pressure. The spring cylinder can be moved with maximum spring travel to its end position because of its larger cross-sectional surface, and the tensioning cylinder pre-tensions the chain with a force that corresponds to the pre-tensioning pressure.

Abstract: The invention relates to a welded profile for fitting a digger with a hoe bucket or loading shovel, such as a boom or stanchion, comprising upper and lower webs and sidewalls cooperating therewith, whereby the sidewalls are provided with upper and lower profile reinforced end regions which form the corner regions for the upper and lower webs arranged between the end regions.